Hydraulic Axial Piston Pump

The axial hydraulic piston pump has a series of cylinders mounted parallel to the axis of rotation. (The arrangement is similar to shell chambers in a revolver.) Hydraulic pistons are installed in the cylinders. Each hydraulic piston has a spherical end that mounts in a shoe.

The shoe is held against a swashplate by a spring in the cylinder block. The swashplate remains stationary as the cylinder block rotates with the input shaft. When the swash plate is at an angle to the shaft, it moves the hydraulic pistons back and forth in the cylinders as the cylinder block rotates. This movement provides the “pumping action.”